JP2008258463A - Permanent magnet material and permanent magnet using the same, and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a permanent magnet having temperature characteristics superior than those of an Nd<SB>2</SB>Fe<SB>14</SB>B-based magnet and having saturation magnetization higher than that of Sm<SB>2</SB>Fe<SB>17</SB>N<SB>x</SB>, a manufacturing method therefor, and a permanent magnet material used therefor. <P>SOLUTION: This permanent magnet material contains 10-95 mass% of an Sm<SB>2</SB>Fe<SB>17-x</SB>M<SB>x</SB>N<SB>y</SB>based magnet powder (where M is at least one or more kinds selected from among Mn, Co, Zr, Al, Ga, Ta, Nb, Ti, and x=0-3, y=1-4), and 90-5 mass% of a ferromagnetic material exhibiting saturation magnetization value not less than 1.4 T singly. The permanent magnet is obtained by mixing a binder into the permanent magnet material and solidifying it. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention provides a thermally stable bond magnet powder, bond magnet, or metal binder magnet having excellent magnetic properties such as saturation magnetization and coercive force.

Currently, Nd ₂ Fe ₁₄ B-based magnets have the largest production value and the highest characteristics among rare earth magnets, but these magnets are thermally unstable, and the magnetic characteristics deteriorate as the temperature rises. Have the disadvantages. Therefore, the maximum use temperature is about 150 ° C. and cannot be used in an environment where the temperature is high.

Therefore, in a high temperature environment of 150 ° C. or higher, there are currently only options for Co-based magnets (Sm ₂ Co _17- based magnets, SmCo _5- based magnets, FeCrCo-based magnets) and Sm ₂ Fe ₁₇ N _x- based bonded magnets. Among them, the Co-based magnet has the disadvantage that it is inferior in magnetic properties and is expensive, and since it is brittle, it has the disadvantage that cracks and cracks are likely to occur, and Sm ₂ Fe ₁₇ N _x has high magnetic properties, but it is about There is a disadvantage that a disproportionation reaction is caused at 500 ° C. or more, and it is decomposed into SmN + αFe. Therefore, sintering is generally impossible. For this reason, Sm ₂ Fe ₁₇ N _x- based magnets cannot be sintered, and as a product, only bonded magnets are used, which are generally expensive and have characteristics that are lower in properties than sintered bodies.

  Further, Patent Document 1 describes a hybrid magnet in which ferrite magnetic powder is mixed with rare earth magnet powder. However, the method of mixing this ferrite has a small saturation magnetization, and a large improvement in magnetic characteristics cannot be expected. Currently. In addition, nanocomposite magnets made by melt spinning method (rapid solidification method) are isotropic powders, and it is difficult to control the precipitation phase, so this also cannot be expected to greatly improve magnetic properties.

JP 2003-59706 A

Therefore, the technical problem of the present invention is that a permanent magnet that is superior in temperature characteristics to an Nd ₂ Fe ₁₄ B-based magnet and has a saturation magnetization higher than that of Sm ₂ Fe ₁₇ N _{x, a} manufacturing method thereof, and a permanent magnet material used therefor And to provide.

Another technical problem of the present invention is that a highly anisotropic Sm ₂ Fe ₁₇ N _x magnet powder is included, so that the BH loop and the like do not have two stages, and a square-shaped relatively good permanent magnet is obtained. It is in providing the manufacturing method and the permanent magnet material used for it.

According to the present invention, Sm ₂ Fe _17-x M _x N _y- based magnet powder (where M is at least one selected from Mn, Co, Zr, Al, Ga, Ta, Nb, Ti, x = 0 .About.3, y = 1 to 4) is contained in an amount of 10 to 95% by mass, and a ferromagnetic material having a saturation magnetization value of 1.4 T or more alone is contained in an amount of 90 to 5% by mass. A magnet material is obtained.

  According to the present invention, in the permanent magnet material, the composition of the ferromagnetic material to be contained contains 50 mass% or more of Fe, and Co, Cr, Ni, V, Mo, Mn, W, Al, Zn , C, Si, B and Y contain at least one element in an amount of 0 to 50% by mass (in the case of 0, Fe is 100% by mass), thereby obtaining a permanent magnet material.

  According to the invention, in the permanent magnet material, the composition of the ferromagnetic material to be contained contains 50 mass% or more of Co, Fe, Cr, Ni, V, Mo, Mn, W, Al, Zn , C, Si, B, and Y contain at least one element in an amount of 0 to 50% by mass (in the case of 0, Co is 100% by mass), thereby obtaining a permanent magnet material.

  According to the present invention, in the permanent magnet material according to any one of the above, the ferromagnetic material is a magnetic powder having an average particle diameter (D50) in the range of 30 nm to 150 μm, or The shape has a fine wire (or wire) or needle shape, and the fine wire or needle powder contains at least one of magnetic powders having an average wire diameter of 20 nm to 50 μm and a length of 5 mm or less. A characteristic permanent magnet material is obtained.

  In addition, according to the present invention, there is obtained a permanent magnet obtained by molding and solidifying a mixture having any one of the above permanent magnet materials and a polymer binder of 5 volume% to 40 volume%. It is done.

  Further, according to the present invention, a molded body of any one of the permanent magnet materials and a mixture containing 5% to 40% by volume of a metal binder having a melting point of 500 ° C. or less is formed in vacuum or non-oxidized. A permanent magnet obtained by heat treatment and solidification at 500 ° C. or lower in a neutral atmosphere is obtained.

  In addition, according to the present invention, an admixture is obtained by adding and mixing a polymer binder to any one of the permanent magnet materials so that the ratio after mixing is 5 volume% to 40 volume%. A method for producing a permanent magnet is provided, which includes a mixing step, a forming step of forming the mixture to obtain a formed body, and a solidifying step of solidifying the formed body.

  According to the present invention, any one of the permanent magnet materials is mixed with a metal binder having a melting point of 500 ° C. or lower so as to be 5% by volume to 40% by volume to obtain an admixture; There is obtained a method for producing a permanent magnet comprising a molding step obtained by molding the mixture, and a heat treatment step in which the molded body is heat-treated in a temperature range of 500 ° C. or lower.

  According to the present invention, any one of the permanent magnet materials is mixed with a metal binder having a melting point of 500 ° C. or lower so as to be 5% by volume to 40% by volume to obtain an admixture; There is obtained a method for producing a permanent magnet, comprising a step of forming the molded body in a temperature range of 500 ° C. or lower to obtain a molded body.

  In addition, according to the present invention, in the method for manufacturing any one of the above permanent magnets, there is obtained a method for manufacturing a permanent magnet, wherein the forming step is performed in a magnetic field.

According to the present invention, by mixing ferromagnetic powder or ferromagnetic wire with high saturation magnetization and Sm ₂ Fe ₁₇ N _x- based magnet powder, the saturation magnetization becomes higher than that of Sm ₂ Fe ₁₇ N _x before mixing, which is superior. Show magnetic properties. This makes it possible to produce an excellent magnet that satisfies high coercivity, high saturation magnetization, and high thermal characteristics.

The ferromagnetic material used for this magnet needs to have a higher saturation magnetization than Sm ₂ Fe ₁₇ N _x- based magnet powder, and Fe, Co, Fe-based alloy, Co-based alloy, Or a mixture thereof.

Further, according to the present invention, since the anisotropy of the Sm ₂ Fe ₁₇ N _x magnet powder is large, the BH loop or the like does not have two stages, and the square-shaped relatively good permanent magnet, its manufacturing method, A permanent magnet material using can be provided.

  The present invention will be described in more detail.

Fe, Co, or Fe-based alloy, Co-based alloy, or a mixture thereof having higher saturation magnetization than 1.4T (commercially available) which is the saturation magnetization of Sm ₂ Fe ₁₄ N _x is converted into Sm ₂ Fe ₁₇ N _x. High magnetic properties are obtained by mixing with system magnet powder. Further, the higher the saturation magnetization of these Fe, Co, or Fe-based alloy, or Co-based alloy mixed, the larger the coercive force, or the smaller the average particle size, the more the final permanent magnet. This improves the properties and can be an excellent magnet.

In addition, by changing the ratio of the Sm ₂ Fe ₁₇ N _x- based magnet powder and the ferromagnetic powder, the saturation magnetization and the coercive force can be arbitrarily adjusted to flexibly correspond to the magnetic characteristics required for the product. be able to.

As the ratio of this change, the ratio of the Sm ₂ Fe ₁₇ N _x (X = 1 to 4) magnet powder to the ferromagnetic powder is 10 Sm ₂ Fe ₁₇ N _x (X = 1 to 4) magnet powder. When the content is ˜95% by mass and the ferromagnetic powder is contained by 90 to 5% by mass, good characteristics can be obtained.

When the ratio of the ferromagnetic powder is higher than 90% by mass, there is no advantage over the Fe-Cr-Co magnet etc. from the viewpoint of coercive force and maximum energy product, and the ratio of the ferromagnetic powder is more than 5% by mass. When the amount is small, the characteristics are almost the same as in the case of using only the Sm ₂ Fe ₁₇ N _x powder, and no superiority appears.

  The ferromagnetic material to be added is a magnetic powder having an average particle diameter (D50) in the range of 30 nm to 150 μm, or has a fine line (or wire) or needle shape, and the fine line or needle The average wire diameter of the powder must be in the range of 20 nm to 50 μm. When the particle diameter / wire diameter is smaller than this range, production and handling are difficult, density is difficult to increase, and superparamagnetism is dominant in magnetic properties. Further, when the particle diameter / wire diameter is larger than this range, the hysteresis curve has two steps, and the residual magnetic flux density, squareness, and maximum energy product are greatly deteriorated.

  Moreover, as a binder of these magnet powders, that is, a binder, a polymer and a metal are considered. The type of polymer binder used in the present invention is a thermosetting resin such as phenol resin, polyester resin, epoxy resin, urea resin, melamine resin, or polyethylene resin, polypropylene resin, PVC, ABS, acrylic, styrene, Thermoplastic resins such as polycarbonate, nylon, polyacetal, and polyester are conceivable and need to be properly used depending on the application.

As the types of metal binders, Zn-based alloys, Bi-based alloys, Pb-based alloys, Ga-based alloys, In-based alloys, or single metals thereof can be considered, but Sm ₂ Fe ₁₇ N _x is not suitable at about 500 ° C. In order to cause a leveling reaction, the metal binder must also have a melting point of 500 ° C. or lower.

As a method of forming a permanent magnet from a mixture of these binder and magnet powder, it is conceivable that the permanent magnet is formed by compression molding, extrusion molding, or injection molding. These moldings can be performed either in a magnetic field or in a non-magnetic field. But it is possible. In the case of a metal binder, hot working is also conceivable. At that time, since Sm ₂ Fe ₁₇ N _x causes a disproportionation reaction at about 500 ° C., it is necessary to perform hot working at 500 ° C. or less.

By mixing a ferromagnetic powder or a ferromagnetic wire with a saturation magnetization higher than 1.4T (commercial product) which is a saturation magnetization of Sm ₂ Fe ₁₄ N _x with a Sm ₂ Fe ₁₇ N _x magnet powder, The saturation magnetization is higher than that of Sm ₂ Fe ₁₇ N _x . Further, since the anisotropic magnetic field and coercive force of the Sm ₂ Fe ₁₇ N _x- based magnet powder are large, the coercive force decrease due to the mixing of these soft magnetic powders is relatively small, and the coercive force necessary for use as a magnet is required. Magnetic force can be secured.

  This makes it possible to produce an excellent magnet that satisfies high coercivity and high saturation magnetization.

The ferromagnetic material used for the permanent magnet is required to have a higher saturation magnetization than the Sm ₂ Fe ₁₇ N _x- based magnet powder, and Fe, Co, Fe-based alloy or Co-based alloy is a material satisfying this condition. Or mixtures thereof. Further, since the anisotropy of the Sm ₂ Fe ₁₇ N _x magnet powder is large, the BH loop or the like does not have two stages, and a square-shaped relatively good magnet can be obtained.

  Examples of the present invention will be described below.

Example 1
The ferromagnetic powder mixed with the Sm ₂ Fe ₁₇ N _x powder is an Fe powder having an average particle size of 80 nm, and was prepared by decomposing a carbonyl Fe solution with ultrasonic waves. The ratio of Fe powder to Sm ₂ Fe ₁₇ Nx (Fe powder: Sm ₂ Fe ₁₇ N _x powder) = (100 mass%: 0 mass%), (90 mass%: 10 mass%), (30 mass%: 70 (Mass%), (5% by mass: 95% by mass), and (0% by mass: 100% by mass), respectively, were measured using an electronic balance, and mixed in an argon atmosphere / dry ball mill for 30 minutes.

Thereafter, the powder is taken out, 5% by mass of an epoxy resin is added and mixed by hand, and this is put into a cylindrical mold having a diameter of 12 mm and subjected to compression molding with a magnetic field orientation press (orientation magnetic field H = 1185 kA / m) at a pressure of about 490 MPa. Went. Thereafter, the pressed body was cured at 120 ° C. for 30 minutes in the air, and the sample was subjected to magnetic measurement with a BH tracer. The result is shown in FIG. FIG. 1 shows a 4πI-H curve at each composition ratio. From FIG. 1, when Fe is added to Sm ₂ Fe ₁₇ N _x , the coercive force decreases according to the added amount, but the saturation magnetization increases.

  Table 1 below shows the maximum energy products for A to E.

Even in the sample added with 30% Fe, (BH) max increased, and the overall characteristics of the magnet increased. Further, even in the sample in which 90 mass% of Fe of D is added, iHc = 58 kA / m and the coercive force are small, but Br is very large, 1.7 times that of Sm ₂ Fe ₁₇ N _x alone. . (BH) max is larger than alnico magnets currently on the market and Fe—Cr—Co magnets, and can be a practically superior magnet depending on the application.

From the above experiment, the Sm ₂ Fe ₁₇ N _x (X = 1 to 4) -based magnet powder (including the Sm ₂ Fe _17-X Mn _X N _Y- based magnet) is contained in an amount of 10 to 95% by mass, and Fe It has been clarified that the magnet powder containing 90 to 5% by mass of the powder is very practical and can be an excellent magnet.

  In this example, Fe powder was used, but Co powder, Fe-Co alloy powder, Fe-Co-Ni alloy powder, Fe-Cr-Co alloy powder (iron-chromium magnet powder), Fe -Cr-Co-Mo-V alloy powder, Fe-Al-Ni-Co-Cu-Nb-Ti alloy powder (Alnico magnet powder), Fe-Co-WC system alloy powder (KS steel), Fe-Ni -Al alloy (MK steel), Fe-Co-Y alloy powder, Co-Zn alloy powder, Fe-Si alloy powder, Fe-Si-B amorphous alloy powder, Fe-Co-Zr-Ti-Nb-Si It has been confirmed that ferromagnetic alloy powders such as -Ga amorphous alloy also show good characteristics.

  In addition, it can be easily estimated that the same result can be obtained even in a similar composition using these mixed powders or the above elements.

(Example 2)
In the permanent magnet according to the example of the present invention, the powder used is an Fe powder having an average particle size of 30 nm, 1 μm, 150 μm, and 500 μm, and the ratio of each Fe powder to Sm2Fe17Nx (Fe powder: Sm ₂ Fe ₁₇ N _x powder) = (30% by mass: 70% by mass), respectively, was measured using an electronic balance, and mixed in an argon atmosphere / dry ball mill for 30 minutes.

After that, the powder is taken out, 4% by mass of epoxy resin is added, mixed by hand, put into a φ12mm cylindrical mold, and subjected to compression molding by magnetic field orientation press (orientation magnetic field H = 1185 kA / m) with a pressure of about 490 MPa. Went. Thereafter, the pressed body was cured at 120 ° C. for 30 minutes in the air, and the sample was subjected to magnetic measurement with a BH tracer. The result of summarizing the characteristics is shown in FIG. FIG. 2A shows the Fe particle size dependence of the magnetic properties (Br, Ms, SQ), and FIG. 2B shows the Fe particle size dependence of the magnetic properties (iHc, SQ). In FIGS. 2A and 2B, the point shown above the particle size of 1000 μm is not the powder of 1000 μm but the characteristics of the original Sm ₂ Fe ₁₇ N _x .

  Ms increased with increasing Fe particle size, but Br decreased. This indicates that the decrease in magnetization in the first quadrant is large.

  In addition, the demagnetization curve becomes two steps as the particle size increases, and the SQ value (= Br × iHc and the area ratio of the demagnetization loop in the second quadrant), which is a square index, is greatly reduced.

  The reason why Ms increases as the particle size increases includes a decrease in the surface oxidation ratio of Fe powder and an increase in density.

In the case of Fe powder having an average particle diameter of 150 μm, the remanent magnetization Ms is about 10 mT larger than Sm ₂ Fe ₁₇ N _x , and when used in a high permeance shape, superiority is obtained over Sm ₂ Fe ₁₇ N _x powder alone. Can be considered.

The powder with an average particle diameter of Fe of 500 μm is almost the same as the original Sm ₂ Fe ₁₇ N _x in the residual magnetic flux density Br, and there is no superiority in other characteristics.

Therefore, when the average particle diameter (D50) of 30 nm to 150 μm was added, it was revealed that there is a possibility of being superior to Sm ₂ Fe ₁₇ N _x before the addition and an excellent magnet.

(Example 3)
The soft magnetic powder used in Example 3 is a mixed powder of Co wire (or needle-like powder) and Fe wire (or needle powder), and the average wire diameter of the mixed powder is 20 nm, 200 nm, 1 μm. , 50 μm, 200 μm, and the average line length was 50 nm to 2 mm The samples of 20 nm and 200 nm were obtained by thermally decomposing a mixed gas of carbonyl Fe, carbonyl Co gas and Ar gas, and depositing it on the surface of the permanent magnet. Samples of 1 to 200 μm were obtained by purchasing commercially available products.

The Sm ₂ Fe ₁₇ N _x powder was manufactured by Sumitomo Metal Mining.

Respective Fe / Co wires, Sm ₂ Fe ₁₇ N _x and Zn (average particle size 3 μm) are represented by (Fe / Co wire: Sm ₂ Fe ₁₇ N _x powder: Zn) = (40 mass%: 40 mass%: 20 (Mass%), each was measured using an electronic balance and mixed for 1 hour in an argon atmosphere using a V-type mixer. The pulverized and mixed powders were subjected to magnetic field orientation pressing in an Ar atmosphere at 196 MPa.

  This pressed body was further hot-pressed in an Ar atmosphere at 420 ° C. and 686 MPa, and the obtained magnet was magnetically measured with a BH tracer. 3A shows the dependence of the magnetic properties (Br, Ms, SQ) on the Fe / Co wire diameter ratio, and FIG. 2B shows the dependence of the magnetic properties (iHc, SQ) on the FeFe / Co wire diameter ratio. FIG.

3 (a) and 3 (b), the point shown above the particle size of 1000 μm is not a powder of 1000 μm, but when Fe is not added ((Fe / Co wire: Sm ₂ Fe ₁₇ N _x powder: Zn ) = (0 mass%: 80 mass%: 20 mass%))).

3 (a) and 3 (b), Ms increased as the Fe / Co wire diameter increased. The reason why Ms increases as the wire diameter increases includes a decrease in the surface oxidation ratio of the Fe / Co wire and an increase in density. Br, when a powder having an Fe / Co wire diameter of 20 nm to 50 μm was added, exceeded that when no Fe was added (only Sm ₂ Fe ₁₇ N _x + Zn), and showed excellent magnetic properties.

  However, Br decreased with increasing Fe / Co wire diameter. This indicates that the decrease in magnetization in the first quadrant is large as the wire diameter increases.

  In addition, the demagnetization curve becomes two steps as the Fe / Co wire diameter increases, and the SQ value (= Br × iHc, the area ratio of the 4πI-H loop in the second quadrant to Br × iHc) also decreases greatly. did.

In the case of a wire with an Fe / Co wire diameter of 200 μm, Br is much lower than when Fe is not added (only Sm ₂ Fe ₁₇ Nx + Zn), and there is no superior magnetic property, and iHc is also larger than when the Fe / Co wire diameter is 50 μm. Decrease, hysteresis curve becomes large and the square shape deteriorates, and no superiority can be found compared to when no Fe is added as a magnet.

  From the above results, it was revealed that when a wire having an average wire diameter (D50) of 20 nm to 50 μm was added, an excellent magnet could be obtained.

  It is considered that the Fe / Co wire diameter should be determined in consideration of cost, magnetic characteristics, product permeance coefficient, and the like.

  In this example, Fe / Co wire was used, but Fe-Co alloy wire, Fe-Co-Ni alloy needle powder, Fe-Cr-Co-Mo-V alloy needle powder, Fe-Si-Al. (Sendust) Alloy flat powder, Fe-Si-B amorphous alloy wire, Fe-Co-Zr-Ti-Nb-Si-Ga amorphous alloy wire, etc. Although it was conducted, it has been confirmed that it exhibits good characteristics as well.

  In addition, if the average length of the wire exceeds 5 mm, the degree of orientation significantly decreases due to bending or entanglement at the time of mixing, so that the magnetic properties are greatly deteriorated, and the forming ability also decreases. A thickness of 5 mm or less is considered appropriate.

  As described above, the permanent magnet material according to the present invention is used in a thermally stable permanent magnet and a manufacturing method thereof.

The 4 (pi) I-H curve in each composition ratio of the permanent magnet which concerns on Example 1 of this invention is shown. (A) is a figure which shows the Fe particle size dependence of the magnetic characteristic (Ms, Br, SQ) of the permanent magnet which concerns on Example 2 of this invention, (b) is the magnetism of the permanent magnet which concerns on Example 2 of this invention. It is a figure which shows the Fe particle size dependence of a characteristic (iHc, SQ). (A) is a figure which shows the Fe / Co wire diameter dependence of the magnetic characteristic (Ms, Br, SQ) of the permanent magnet concerning Example 3 of this invention, (b) is the permanent magnet concerning Example 3 of this invention. It is a figure which shows the Fe / Co wire diameter dependence of the magnetic characteristic of (iHc, SQ).

Claims (10)

Sm ₂ Fe _17-x M _x N _y- based magnet powder (where M is at least one selected from Mn, Co, Zr, Al, Ga, Ta, Nb, Ti, x = 0 to 3, y = 1 A permanent magnet material comprising 10 to 95% by mass of -4) and 90 to 5% by mass of a ferromagnetic material having a saturation magnetization value of 1.4 T or more as a single substance.   The permanent magnet material according to claim 1, wherein the composition of the ferromagnetic material to be contained contains 50 mass% or more of Fe, and Co, Cr, Ni, V, Mo, Mn, W, Al, Zn, C, A permanent magnet material comprising 0 to 50% by mass of at least one element of Si, B and Y (Fe is 100% by mass in the case of 0).   The permanent magnet material according to claim 1, wherein the composition of the ferromagnetic material to be contained contains 50 mass% or more of Co, Fe, Cr, Ni, V, Mo, Mn, W, Al, Zn, C, A permanent magnet material containing 0 to 50% by mass of at least one element of Si, B and Y (Co is 100% by mass in the case of 0).   4. The permanent magnet material according to claim 2, wherein the ferromagnetic material is a magnetic powder having an average particle diameter (D50) in a range of 30 nm to 150 μm, or has a fine line or needle shape. And the permanent magnet material characterized by including at least any one of the magnetic powder whose average wire diameter of the fine wire or needle-like powder is 20 nm-50 micrometers and whose length is the range of 5 mm or less.   A permanent magnet formed by molding and solidifying a mixture comprising the permanent magnet material according to any one of claims 1 to 4 and a polymer binder of 5% to 40% by volume. .   A molded body of a mixture containing the permanent magnet material according to any one of claims 1 to 4 and a metal binder having a melting point of 500 ° C or lower in a range of 5% by volume to 40% by volume in a vacuum, or A permanent magnet obtained by heat treatment and solidification at 500 ° C. or less in a non-oxidizing atmosphere.   An admixture obtained by adding and mixing a polymer binder to the permanent magnet material according to any one of claims 1 to 4 so that a ratio after mixing is 5 vol% to 40 vol%. The manufacturing method of the permanent magnet characterized by having the mixing process which obtains, the shaping | molding process which shape | molds the mixture, and obtains a molded object, and the solidification process which solidifies the molded object.   A mixing step of mixing the permanent magnet material according to any one of claims 1 to 4 with a metal binder having a melting point of 500 ° C or lower so as to be 5% by volume to 40% by volume to obtain an admixture. And a molding process obtained by molding the mixture, and a heat treatment process in which the molded body is heat-treated in a temperature range of 500 ° C. or lower.   A mixing step of mixing the permanent magnet material according to any one of claims 1 to 4 with a metal binder having a melting point of 500 ° C. or less so as to be 5% by volume to 40% by volume to obtain an admixture; A method for producing a permanent magnet, comprising a step of forming the molded body in a temperature range of 500 ° C. or lower to obtain a molded body.   The method for manufacturing a permanent magnet according to any one of claims 7 to 9, wherein the compacting step is performed in a magnetic field.

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